Fluvial avulsion is an important process in the dynamics of the riverscapes and plays a key role in the drainage network evolution in lowland areas, also influencing past and present social processes and economic activities. Crevasse splays represent significant geomorphological features for understanding the fluvial morphodynamics in lowland areas dominated by avulsion processes. Within wide floodplains characterized by very low elevation ranges, the detection and accurate mapping of crevasse splay morphology and features, such as crevasse channels, levees, and deposit, can be very challenging considering floodplain extension, anthropic impact on the natural channels network, logistic difficulties, and in some cases, climate conditions that prevent field work. This research aims at improving the detection and mapping of crevasse splays in lowland areas through the combination of different remote sensing techniques based on optical multispectral imagery and topographic data derived from satellite earth observation missions. The Lower Mesopotamia Plain (LMP) offers a unique opportunity to study the avulsion processes because it presents numerous examples of crevasse splays, characterized by different sizes and states of activity. Furthermore, in this area, a strong correlation exists between the formation and development of crevasse splays and the expansion of agriculture and early societies since the Early Holocene. Different supervised classification (SC) methods of Landsat 8 satellite images have been tested together with topographic analysis of the microrelief, carried out based on two different 1-arcsec DEMs (AW3D30 and GDEM2). The results of this study demonstrate that the combination of multispectral imagery analysis and topographic analysis of the microrelief is useful for discerning different crevasse elements, distinguishing between active and relict landforms. The methodological approach proved helpful for improving the mapping of erosional and depositional landforms generated by the avulsion process and, in the study area, provided the best results for the active landforms.

Rock slopes involved in extensive landslide processes are often characterized by complex morphodynamics acting at different scales of space and time, responsible for different evolutionary scenarios. Mass Rock Creep (MRC) is a critical process for long-term geomorphological evolution of slopes and can likewise characterize actively retreating coastal cliffs where, in addition, landslides of different typologies and size superimpose in space and time to marine processes. The rocky coast at the Conero promontory (central Adriatic Sea, Italy) offers a rare opportunity for better understanding the predisposing role of the morphostructural setting on coastal slope instability on a long-time scale. In fact, the area presents several landslides of different typologies and size and state of activity, together with a wide set of landforms and structural features effective for better comprehending the evolution mechanisms of slope instability processes. Different investigation methods were implemented; in particular, traditional geomorphological and structural field surveys were combined with land surface quantitative analysis based on a Digital Elevation Model (DEM) with ground-resolution of 2 m. The results obtained demonstrate that MRC involves the entire coastal slope, which can be zoned in two distinct sectors as a function of a different morphostructural setting responsible for highly differentiated landslide processes. Therefore, at the long-time scale, two different morphodynamic styles can be depicted along the coastal slopes that correspond to specific evolutionary scenarios. The first scenario is characterized by MRC-driven, time-dependent slope processes involving the entire slope, whereas the second one includes force-driven slope processes acting at smaller space–time scales. The Conero promontory case study highlights that the relationships between slope shape and structural setting of the deforming areas are crucial for reaching critical volumes to induce generalized slope collapse as the final stage of the MRC process. The results from this study stress the importance of understanding the role of morphostructures as predisposing conditions for generalized slope failures along rocky coasts involved in MRC. The findings discussed here suggest the importance of the assessment of the slope instability at the long time scale for a better comprehension of the present-day slope dynamics and its major implications for landslide monitoring strategies and the hazard mitigation strategies.

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<p>The question of human-waterscape interactions worldwide has been and still is a central topic in historical and archaeological research. The Southern Mesopotamia Plain, where the ancient State of Lagash developed, represents an ideal case study. Indeed, at Tell Zurghul archaeological site, extensive field-works have been recently carried on by the Italian Archaeological Mission and an interdisciplinary approach, combining field surveys and geomorphological mapping through remote sensing techniques, has been applied for analyzing the function and role of the waterscape on the early civilization. Indeed, the geomorphological analysis through remote sensing techniques and archaeological surveys are essential for the reconstruction of a complex environmental system, where landforms due to different morphogenetic processes occur, related to the presence of a wide fluvial-deltaic paleo-system and the human activities.</p><p>The Southern Mesopotamian Plain coincides with the Tigris and Euphrates deltaic plain, developed starting since the Mid-Holocene: the maximum marine ingression reached Nasiriyah and Al-Almara about 6000 yrs BP; after that, the paleo-delta progradation shifted the shoreline up to the modern position. The development of a typical bird-foot delta guaranteed an amount of water indispensable for agriculture, settlements, and transport. Indeed, the high mobility of the channels and avulsions processes (i.e. levees breaks and related crevasse splays formation) are the main features typically connected to a multi-channel system, guarantying the water supply through seasonal floods. In the area, the management of water during the mid-Holocene, digging an extensive network of canals and building dams, improved the socio-economic conditions. However, the occurrence of the so-called Megadrought Event, dated 4.2 ka BP, drastically modified the hydroclimatic conditions of the area, favoring arid conditions and improving the frequency of unpredictable extreme hydrological events.</p><p>The main aim of the work is to contribute to the reconstruction of the waterscape surrounding the archaeological sites of Tell Zurghul and Lagash and know more about waterscape-human interactions during the Holocene. A multi-sensor approach has been adopted to identify the main geomorphological features and describe the associated morphogenetic processes. The availability of the multispectral Landsat-8 satellite imagery and 30-meter spatial resolution DEMs (i.e. the optical DSM from ALOS and the infrared DTM from ASTER) allowed a supervised classification through specific spectral signature and a microtopographic analysis. The spectral signatures of active and inactive crevasse splays have been extracted, discerning among crevasse channels, proximal and distal deposits characterized by coarsest and finest sediment respectively. Moreover, the microtopographic analysis led to recognize channels above inter-floodplains, upward convexity of active crevasse splays and roughly flat topography of inactive ones. The excavations in Area B of the archaeological site shows evidence of the presence of water and the proximity of the sea. Brackish-marine marshes environment has been confirmed by fish vertebras (belong to “Bull Shark”, i.e. <em>Carcharhinus leucas</em>) and fishing net recovered into a mudbrick structure. Moreover, the patron deity of the city in the 3<sup>rd</sup> millennium BC, was the goddess of the sea and sea species (fish and birds), confirming the strong connection between water and the ancient settlement.</p>